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Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings were grown for 50 days in growth chambers in an ambient or twice ambient carbon dioxide concentration ([CO2]) at a day/night temperature of 19/12 degrees C or 23/16 degrees C. Although elevated [CO2] (EC) had only slight effects on the growth parameters measured, elevated temperature (ET) increased above ground dry mass of both species. Among treatments, biomass accumulation of both species was greatest in the combined EC + ET treatment. The EC treatment induced thylakoid swelling and increased numbers of plastoglobuli observed in Scots pine needles. Although EC had little effect on Rubisco protein or N concentration of needles, ET had a large effect on N-containing compounds and enhanced N allocation from 1-year-old needles. Terpenoids were more responsive to EC and ET than total phenolics. Generally, terpene concentrations were reduced by EC and increased by ET. Increased terpenoid concentrations in response to ET might be associated with thermotolerance of photosynthesis. In Norway spruce, EC decreased total phenolic concentrations in needles, probably as a result of increased growth. We conclude that, in seedlings of these boreal species, the effects of elevated [CO2] on the studied parameters were small compared with the effects of elevated temperature. 相似文献
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P. Peltonen-Sainio M. Granqvist A. Säynäjärvi 《Journal of Agronomy and Crop Science》1993,171(4):268-273
Contribution of nitrogen (N) and plant breeding to yield formation of oats ( Avena sativa L.) was evaluated with two years'field experiments. These consisted of four Finnish oat cultivars released between 1935 and 1988 and one breeding line. Three rates of N application were used (0, 90, and 120 kg N ha−1 ) and 19 morpho-physiological traits, including maturity class, plant structure and plant stand structure, were assessed.
The modern cultivar out-yielded the old one under low and high N, indicating that return of old varieties into cultivation under low-input conditions is unlikely to be feasible. An oat ideotype for low productivity conditions must be characterized. Furthermore, N contributed more than oat breeding to several traits studies. However, in some cases N appeared to affect the traits measured in a negative manner. Use of N increased production of both above-ground vegetative biomass and panicle weight without changing HI significantly. However, plant breeding slightly reduced the production of vegetative phytomass and increased the grain: straw ratio by 10 %. Moreover, genetic gains in shortening straw length, increasing lodging resistance, and improving BYDV tolerance were partly lost when high rates of N application were used. The contribution of N and oat breeding to other morpho-physiological traits is discussed. 相似文献
The modern cultivar out-yielded the old one under low and high N, indicating that return of old varieties into cultivation under low-input conditions is unlikely to be feasible. An oat ideotype for low productivity conditions must be characterized. Furthermore, N contributed more than oat breeding to several traits studies. However, in some cases N appeared to affect the traits measured in a negative manner. Use of N increased production of both above-ground vegetative biomass and panicle weight without changing HI significantly. However, plant breeding slightly reduced the production of vegetative phytomass and increased the grain: straw ratio by 10 %. Moreover, genetic gains in shortening straw length, increasing lodging resistance, and improving BYDV tolerance were partly lost when high rates of N application were used. The contribution of N and oat breeding to other morpho-physiological traits is discussed. 相似文献
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Nissinen A Ibrahim M Kainulainen P Tiilikkala K Holopainen JK 《Journal of agricultural and food chemistry》2005,53(22):8631-8638
The effect of carrot psyllid (Trioza apicalis F?rster) feeding and limonene and methyl jasmonate (MeJA) treatments on the essential oil composition and headspace volatiles of carrot (Daucus carota ssp. sativus), cvs. Parano and Splendid, leaves was studied. Carrot psyllid feeding significantly increased the concentrations of sabinene, beta-pinene, and limonene, whereas limonene treatment increased the concentration of (Z)-beta-ocimene in the leaves of both cultivars. The limonene treatment significantly increased the concentration of total phenolics in the leaves of both cultivars, and MeJA treatment increased phenolic concentration in the leaves of Parano. Exogenous limonene spray did not decrease the number of carrot psyllid eggs laid either 2 or 24 h after treatment. The results suggest that carrot psyllid feeding induces changes in the endogenous monoterpene pool in the carrot leaves. Limonene and MeJA treatments affect some induced defenses of the carrot, but the exogenous limonene spray is not an effective oviposition deterrent against carrot psyllid. 相似文献
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Labelling the salt content in foods: a useful tool in reducing sodium intake in Finland 总被引：1，自引：0，他引：1
OBJECTIVE: To estimate the impact of choosing food products labelled either as low or high in salt on salt intake in the Finnish adult population. SETTING AND SUBJECTS: The National FINDIET 2002 survey with 48-hour recalls from 2007 subjects aged 25-64 years. Sodium intake was calculated based on the Fineli food composition database including the sodium content of natural and processed foods as well as the salt content of recipes. The distribution of salt intake was calculated in different ways: the present situation; assuming that all breads, cheeses, processed meat and fish, breakfast cereals and fat spreads consumed would be either 'lightly salted' or 'heavily salted' based on the current labelling practice; and, in addition, assuming that all foods would be prepared with 50% less or more salt. RESULTS: Excluding underreporters, the mean salt intake would be reduced by 1.8 g in men and by 1.0 g in women if the entire population were to choose lightly salted products and further by 2.5 and 1.8 g, respectively, if also salt used in cooking were halved. Choosing heavily salted products would increase salt intake by 2.1 g in men and by 1.4 g in women. In the worst scenarios, salt intake would be further increased by 2.3 g in men and by 1.6 g in women. CONCLUSIONS: These calculations show that the potential impact of labelling and giving consumers the possibility to choose products with less salt is of public health importance. In addition, strategies to reduce the salt content of all food groups are needed. 相似文献
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Pivi M. Kanerva Tuula S. Sontag-Strohm Pivi H. Ryppy Pirjo Alho-Lehto Hannu O. Salovaara 《Journal of Cereal Science》2006,44(3):347-352
Immunological methods based on monoclonal antibodies with varying specifities towards gluten proteins have been used to control the purity of gluten-free products. Commercially available methods have been developed to detect gluten proteins found in wheat. However, difficulties have occurred in quantifying barley proteins with the same accuracy as wheat proteins. Barley is also a common contaminant in oat products. In this study, oat flour samples were deliberately contaminated with known amounts of barley flour and analysed using two commercial enzyme linked immunosorbent assays (ELISA). The methods were based on an ω-gliadin antibody and an R5 antibody. The results obtained with the R5 antibody were overestimates while the ω-gliadin antibody underestimated the higher barley prolamin content. This study showed that inaccuracies in ELISA assays in quantifying barley contaminations can possibly be eliminated by using a hordein standard. However, it is necessary to know the source of contamination. This would prevent overestimation of the hordein content of gluten-free products. Overestimation unnecessarily reduces the variety of gluten-free products and may decrease compliance to a gluten-free diet. 相似文献
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Genetic yield improvements in oat (Avena sativa L.) cultivars grown at high latitudes have resulted from marked changes in harvest index and yield components. This study was designed to investigate whether such changes have entailed alterations in duration of different developmental phases: vegetative, generative and grain filling phases and pre-anthesis generative sub-phases such as pre-fertile, pre-abortion, fertile pre-abortion, fertile and abortion sub-phases. We tested 14 oat cultivars released between 1921 and 1988 and 6 breeding lines. Ten randomly sampled plants of each oat entry were collected every 3–4 d (18 times) from seedling emergence until pollination, and apical developmental stages were determined on the most advanced spikelet. Cumulated degree-days (Cdd) for each critical developmental stage and component phases were determined (5 °C as a base temperature). At each measurement the number of leaves, green leaves and tillers on main shoot, apex length (mm) and height to the uppermost node, and stipule (cm) were recorded. Phyllochron (°C d leaf−1) and relative elongation rates (RER) for height characterising traits were calculated. Grain filling was the only period altered by breeding, while no consistent effects on duration of vegetative and generative pre-anthesis phases and sub-phases were detected. Different developmental phases were interrelated: in some cases cultivars with similar duration of pre-anthesis phase, however, differed in duration of some pre-anthesis sub-phases. Their duration was not, however, consistently associated with measured growth and yield parameters. Likely long days that make the northern growing conditions exceptional and unique, substantially narrowed the differences among oat entries in duration of different developmental phases, thereby making their role also less critical in yield determination contrary to the situation in the main global temperate cereal production regions. 相似文献
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Pirjo S.A. Mäkelä Antti Tuulos Marja Turakainen Arja Santanen Frederick L. Stoddard 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):195-201
Abstract Winter turnip rape (Brassica rapa spp. oleifera) is an underutilized crop that deserves to be revitalized for use in high-latitude agriculture. Many crop rotations around the world are dependent on the small-grain cereals, and turnip rape as a break crop, with its range of secondary chemicals, helps to suppress weeds, nematodes and pathogenic fungi. It may be used as an energy crop, it can restrict erosion and nutrient leaching while also improving soil structure and fertility, and it requires relatively low inputs. Although winter turnip rape was once the major oil crop in Finland, in the 1970s it was replaced by spring turnip rape, the lower erucic acid and glucosinolate contents of which made it suitable for food and feed uses. Winter hardiness of the crop could be improved, and industrial end uses, such as lubricants for which high erucic acid content is preferred, targeted in the first instance. Breeding progress would be accelerated by a change from the predominantly self-incompatible breeding system to self-compatibility, now available in modern germplasm, and this would allow use of other rapid breeding methods, such as doubled haploidy. Thus, the many advantages of the winter turnip rape crop would repay its return to agriculture. In this review we will introduce the many utilization possibilities of the crop as well as give background on why more attention and research efforts should be paid towards this crop. We will also indicate some of the array of factors that have a marked role in an attempt to ecologically intensify crop production. 相似文献
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Spring wheat response to timing of water deficit through sink and grain filling capacity 总被引：2，自引：0，他引：2
Ari Rajala Kaija Hakala Pirjo Mkel Susanna Muurinen Pirjo Peltonen-Sainio 《Field Crops Research》2009,114(2):263-271
Water and nitrogen (N) availability are the main factors influencing crop growth globally. Poorly distributed or insufficient water for crop growth requirements decreases yields in drought-prone areas such as those with a Mediterranean type environment. Cereal grain yield is a complex trait of interrelated components: plants per unit land area, spikes per plant, spikelets per spike, grains per spikelet, and single grain weight (SGW). The effect of water limitation and timing on development of yield components was studied in detail at the spike level in spring wheat (Triticum aestivum L.) cultivar Amaretto. An experiment with three watering treatments (control watering, CONT; drought prior to pollination, DR1 and terminal drought, DR2) was arranged in a large greenhouse (20 m × 30 m), with the use of standard field-trial machinery. Automated blackout curtains were used to control day length, which was set to correspond to that at 40°N. With watering treatments, two N application rates (60 and 120 kg N ha−1) were used to investigate the N effect and potential watering × N interaction on yield formation and realisation. The water deficit effect exceeded the effect of N on fertile floret and grain number and SGW. DR1 strongly reduced the number of fertile florets and grains, whereas terminal drought reduced the number of grains per spike. Resuming the watering at pollination markedly enhanced photosynthesis, and hence grain filling capacity, resulting in the highest SGW in DR1. Enhancement in availability of key resources was associated with reduced rate of fertile floret and grain abortion, which resulted in higher grain to fertile floret ratio in DR1. Spikelets in the mid-section of the spike dominated yield formation in all treatments. In DR1 this was especially emphasised as 53% of the grain yield was produced in spikelets 4–6, whereas in DR2 and CONT this was 45 and 41%, respectively. Grains in proximal position in the spikelets produced about 80% of the spike grain yield, the proportion being slightly higher in stressed plants and plants receiving 60 kg N. No marked N × water deficit treatment interaction occurred for any of the measured parameters. 相似文献
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Martti?Ven?l?inenEmail author Anni?M.?Harju Pekka?Saranp?? Pirjo?Kainulainen Markku?Tiitta Pirkko?Velling 《Wood Science and Technology》2004,38(2):109-118
The concentrations of three individual stilbenes, pinosylvin (PS), pinosylvin monomethyl ether (PSM), and pinosylvin dimethyl ether (PSD), and the total concentration of phenolic compounds were determined in 34-year-old Scots pines which were known to have either decay-resistant or susceptible heartwood. The sample trees were selected from two progeny tests among 783 trees; the decay resistance of which had been screened earlier in vitro against a brown-rot fungus Coniophora puteana. Ten decay-resistant and ten susceptible trees from each of the progeny tests were analysed. In the heartwood of the resistant trees, the average total concentration of the stilbenes was 7.5 and 6.4 mg/g of dry weight, while in the heartwood of the susceptible trees the respective values were 5.0 and 4.7 mg/g. The difference between the decay resistant and susceptible trees was statistically significant in both progeny tests. The difference in concentration of total phenolics, analysed by the Folin-Ciocalteu method, was also significant. A high concentration of phenolics was connected to the low hygroscopicity of wood. The results support the argued hypothesis that the stilbenes make a contribution to the differences in the decay rate of natural wood substrate. On the other hand, the results show that the stilbenes alone do not explain the variation in decay rate. 相似文献